Having a small or medium sized company and like to start running a VOIP server? It might be time to look at some options. You can look at the “Response Point” solution from Microsoft or you can look at the opensource asterisk VOIP PBX server.
Ben Brauer and Richard Sprague from Microsoft Research show off Response Point, a new Microsoft technology that makes it easy for small businesses to setup a professional phone system using voice over IP, speech recognition (using the Speech Server voice recognition engine), inbox voice mail, and more, all at a fraction of the cost. As mentioned in the demo, you can actually call Richard's Response Point phone number and try it out yourself!
The opensource asterisk solution might be a little harder to install or manage but it is opensource and is having a very large community to support development and bugfixing.
‘Asterisk is the world's leading open source PBXi, telephony engine, and telephony applications toolkit. Offering flexibility unheard of in the world of proprietary communications, Asterisk empowers developers and integrators to create advanced communication solutions...for free.”
Asterisk is primarily developed on GNU/Linux for x/86 and runs on GNU/Linux for PPC along with OpenBSD, FreeBSD, and Mac OS X. Other platforms and standards-based UNIX-like operating systems should be reasonably easy to port for anyone with the time and requisite skill to do so. Asterisk is available in Debian Stable and is maintained by the Debian VoIP Team.
Asterisk supports a wide range of protocols for the handling and transmission of voice over traditional telephony interfaces including H.323, Session Initiation Protocol (SIP), Media Gateway Control Protocol (MGCP), and Skinny Client Control Protocol (SCCP).
Using the Inter-Asterisk eXchange Voice over IP protocol Asterisk merges voice and data traffic seamlessly across disparate networks. The use of Packet Voice allows Asterisk to send data such as URL information and images in-line with voice traffic, allowing advanced integration of information.
Asterisk provides a central switching core, with four APIs for modular loading of telephony applications, hardware interfaces, file format handling, and codecs. It allows for transparent switching between all supported interfaces, allowing it to tie together a diverse mixture of telephony systems into a single switching network.